The symposium today by the British Medical Association (BMA), follows a climbdown from the union, after a long conflict over changes to doctors’ contracts which followed Government pledges to improve levels of medical cover at weekends.

Dr Ellen McCourt resigned as JDC chairman earlier this month saying her position had become 'untenable'

The new report says cash-strapped NHS trusts cannot afford a wholesale expansion of services to put them on a seven-day footing - and that the public should be warned not to expect one.

“Given the financial realities of the NHS and the wider system, our clear focus must be on those services which have the most impact in terms of outcomes for patients, rather than offering convenience,” said the NHS Confederation, which represents all health service organisations.

Phil McCarvill, the report’s author, said NHS trusts would need to concentrate limited resources on where they were needed most, and the needs of local populations.

While city hospitals might “sweat their assets” by offering patients planned operations and diagnostic tests at weekends, many rural hospitals would not have enough staff to do this, he said.

So far, attempts to improve access to services had found some - such as ante-natal appointments - were popular at weekends, while others were not.

“In some areas hospitals have offered diagnostic tests on Saturdays and Sundays only to find there is not much take-up,” said Mr McCarvill, deputy director of policy.

“Meanwhile, we’ve found really high take-up of ante-natal first scans at weekends, because often at that early stage women didn’t want to book time off work before their employers knew they were pregnant.”

Last year, the Conservative manifesto promised everyone access to a GP seven days a week, from 7am to 7pm.

But the new report highlights poor uptake of appointments in some areas, and warns of funding shortages.

“Given financial pressures on all NHS and wider health and care organisations it is important that we focus on ensuring consistency of outcomes in key parts of the health and care system, starting with those who require urgent and emergency care and those currently in hospital,” the NHS Confederation stated.

The report says debate about seven day services has become “increasingly polarised” because it has been connected to NHS contract negotiations, which resulted in a string of strikes by junior doctors. It says a wider debate about how a seven day NHS is best delivered is now required.

Earlier this month, the BMA lifted all threat of strike action and pledged to work with the Government to help introduce the contract for junior doctors.

On Thursday the Health Secretary will attend a “symposium” hosted by the BMA, to discuss the future of seven-day services with members of the JDC, along with medical royal colleges, patient groups and health care regulators.

A Department of Health spokesperson said: “We are committed to seven-day services so patients get the same high standard of urgent and emergency care throughout the week - this is about safety, not convenience. That’s why we're backing the NHS's own plan for the future by investing £10 billion to transform services.”

Dr Mark Porter, BMA council chairman said: “Patients should have access to high-quality care seven days a week, and NHS staff work around the clock to deliver this.

“With services and frontline staff under more pressure than ever before, we need at look at how patient care can be improved across the week in a sustainable way."

“As the report makes clear, it is vital that we deliver the right care, based on clinical need and that we look at the system in the round, making sure that all areas – from general practice, to hospital, community and social care – are adequately resourced and supported.”